FAQ

Is chukei open source?

Yes. chukei is open source under the Apache License, Version 2.0. You can use, modify, and redistribute it under the terms of the license.

Can chukei serve a wrong (stale) result?

The cache is built to make that an engineering impossibility rather than a hope: only deterministic reads are cacheable, writes invalidate affected tables, chunked results are never cached, and blame mode continuously re-executes a sample of cache hits against live Snowflake and counts mismatches. The SLO is zero; if it ever fires, disable the cache with CHUKEI_PLUGINS_CACHE_ENABLED=false and file a bug — queries keep flowing uncached.

Does chukei see my credentials?

They pass through to Snowflake verbatim. chukei never persists or logs them; session tokens live in memory only. This is enforced by a trace-level credential-leak audit in the test suite.

What happens if chukei crashes?

Clients pointed at it retry, then error — they do not silently fall back. A restart faster than the driver retry budget (~10s) is invisible, and existing sessions resume without re-login. Run with a restart policy (Docker --restart, k8s Deployment) and rehearse the rollback: point the driver host back at <account>.snowflakecomputing.com.

Why isn't my big query cached?

Large results are returned as chunk URLs that drivers download directly from cloud storage, bypassing any proxy — so chukei deliberately never caches chunked responses. They pass through unmodified.

Why did my query miss the cache?

Common reasons: non-deterministic functions (CURRENT_TIMESTAMP(), RANDOM()), a write to a referenced table since the last run, TTL expiry, or differing bind values. When in doubt chukei misses — that's the false-positive-intolerant design.

What's the performance overhead?

Deterministic Rust on the hot path; ~2ms p99 measured locally, with a +5ms budget enforced as an alert threshold (chukei_proxy_overhead_seconds).